Electricity without cables – is there electricity from nothing? RFID microchips
The beginnings of RFID radio transmission technology date back to the 1940s. It was then that the first RFID devices that were used to detect metals in the ground appeared. This technology evolved and quickly became the basis of security systems and anti-theft systems (RFID stickers with a resonant circuit or magnetoacoustic systems began to appear).
The most important and undeniable advantage of RFID technology is the ability to work without separate power sources for both communicating devices. Although of course some devices, usually mobile devices, support RFID transmission while having their own power supply, it is different in the case of RFID tags. Then the energy necessary to start a small electronic system is transmitted through the same electromagnetic field, which ensures proper data transmission between the two devices. What does this mean in practice? In other words, the magnetic field generated by the module's antenna (i.e. a special coil) induces a small current tag in the coil, which is enough to start the system. This small amount of electricity also turns out to be quite sufficient to decode the signal from the transmitter and send a short reply back to the sender. This means that many RFID devices, especially RFID tags, do not need to be powered and still work electrically! Fantastic, isn't it?
RFID chips – two major standards (125 kHz & 13,56 MHz)
The world of RFID devices many years ago split into two main 'factions'. It is about differences in the frequency of operation and the range of possible detection.
The first variant is the 125 kHz radio frequency standard. The second model - intended mainly for proximity devices, i.e. with a range usually a few centimeters - works in the band several dozen times higher (13.56 MHz). Where did such differences come from? They mainly result from the need to distinguish between frequency bands according to the preferred applications.
Different frequency forces not only differences in the design of RFID modules, but also in the dimensions of the antenna itself. For the lower frequency, 125kHz, slightly larger antennas are used, although the form itself (flat air coil) remains the same. It is worth knowing that popular RFID tags come in various forms, depending on the target application. Self-adhesive "pastilles" are ideal for labeling larger objects, while very small objects can be labeled with capsule tags, which resemble a slightly enlarged grain of rice with a diameter of about 2 mm and a length of just over 12 mm.
A RFID modules, RFID tags, NFC readers and much more – Botland
In this category of the Botland store, we have collected a number of practical RFID modules and tags, working in both standards described above. If you need a module for reading 13.56 MHz tags, we especially recommend the Adafruit PN532 module with a built-in PCB antenna and a smaller SM130 Mifare module with two rows of gold pins with UART and I2C interfaces. The well-known RC522 chip, which is the core of the inexpensive and very implementation-friendly ME138 module, will be perfect for basic applications. To support tags with a frequency of 125kHz, we recommend miniature RFID modules ID-12LA from SparkFun and communication modules for systems from the ID-2, ID-3, ID-12, ID-20 series. Of course, our offer includes a wide selection of RFID tags in the form of key rings, cards and capsules.
Today, RFID technology is used for many purposes. RFID has applications in international trade and internet marketing, warehouse processes, return goods management, industry, construction, manufacturing, banking, and security systems. There are even RFID modules that are implanted under the skin (this is a very controversial matter). Anyway - you can use the products in this category for really diverse projects!